Funds are being requested to support the Fourth International Conference on the Varicella-Zoster Virus (VZV). Previous conferences were held in Bethesda, MD, in 1992 (in conjunction with NIH), in Paris, France in 1994, and in Palm Beach, Florida in 1997. The purpose of these meetings is to provide a forum for researchers, academicians, and clinicians involved in VZV research to have a venue for scientific exchange. The meeting is planned to occur March 3-5, 2001 in LaJolla, CA. VZV is the agent that causes varicella (chickenpox) and zoster (shingles), both of which are important pathogens for humans. Zoster is particularly a medical problem for individuals over the age of 50 years in whom it can only be manifested as a skin rash but also may be associated with severe pain that may persist for months to years after the original illness, a condition termed post herpetic neuralgia (PHN). Topics to be discussed in the 2001 meeting will include clinical topics on the first day because the conference begins on a weekend when clinicians are more likely to be available. One session will be devoted to Varicella and the other to Zoster. The first formal sessions will be devoted to treatment and prevention of varicella and zoster, with an emphasis on new developments in vaccines and antiviral drugs. There will be a special workshop on PCR methods by Perkin-Elmer. On the second day, basic aspects of VZV research will be discussed and will include the topics of virus replication, gene regulation, virus-cell protein interaction, animal models, latency, and host responses. There will also be a series of "State of the Art" lectures by experts in the field who have not presented at past meetings. These talks will include a summary of important data presented at the meeting and will attempt to integrate old and new concepts concerning varicella and zoster.